General procedure for the synthesis of 6-fluoro-2-pyridinesulfonamide from 6-fluoro-2-pyridinesulfonyl chloride: 6-fluoro-2-pyridinesulfonyl chloride (2.0875 g, 10.67 mmol) was dissolved in acetonitrile (50 mL) which was pre-cooled to 0 °C, and concentrated ammonia (70 mL, 539 mmol) was added slowly and dropwise. The reaction mixture was stirred at 0 °C for 30 min, then gradually warmed up to room temperature and continued stirring for 2 h. The reaction was completed by concentration reduction under reduced pressure. After the reaction was completed, some acetonitrile was removed by concentration under reduced pressure, and the residue was freeze-dried to obtain the target product, 6-fluoropyridine-2-sulfonamide, as a dark gray solid in 95% yield. The product was analyzed by LC/MS, ESI-MS m/z: 177.0 [M+H]+. 1H NMR (400 MHz, DMSO-d6) δ: 8.26 (q, J = 7.9 Hz, 1H), 7.88 (ddd, J = 7.5, 2.3, 0.6 Hz, 1H), 7.63 (s, 2H), 7.48 (ddd, J = 8.3, 2.4, 0.6 Hz). 2.4, 0.6 Hz, 1H).
